Fix a bug to support %return probe syntax again. Previous commit
4235b04 has a bug which disables the %return syntax on perf probe.
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: linux-kernel@vger.kernel.org
---
tools/perf/util/probe-event.c | 1 +
tools/perf/util/probe-finder.c | 10 ++++++++++
2 files changed, 11 insertions(+), 0 deletions(-)
diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c
index e72f05c..fcc16e4 100644
--- a/tools/perf/util/probe-event.c
+++ b/tools/perf/util/probe-event.c
@@ -1539,6 +1539,7 @@ static int convert_to_probe_trace_events(struct perf_probe_event *pev,
goto error;
}
tev->point.offset = pev->point.offset;
+ tev->point.retprobe = pev->point.retprobe;
tev->nargs = pev->nargs;
if (tev->nargs) {
tev->args = zalloc(sizeof(struct probe_trace_arg)
diff --git a/tools/perf/util/probe-finder.c b/tools/perf/util/probe-finder.c
index 5251366..9b0e1b1 100644
--- a/tools/perf/util/probe-finder.c
+++ b/tools/perf/util/probe-finder.c
@@ -783,6 +783,16 @@ static int convert_probe_point(Dwarf_Die *sp_die, struct probe_finder *pf)
/* This function has no name. */
tev->point.offset = (unsigned long)pf->addr;
+ /* Return probe must be on the head of a subprogram */
+ if (pf->pev->point.retprobe) {
+ if (tev->point.offset != 0) {
+ pr_warning("Return probe must be on the head of"
+ " a real function\n");
+ return -EINVAL;
+ }
+ tev->point.retprobe = true;
+ }
+
pr_debug("Probe point found: %s+%lu\n", tev->point.symbol,
tev->point.offset);
--
